Lithium-ion cells have a positive electrode, referred to as the cathode, and a negative electrode, referred to as the anode, onto which the lithium-ions are reversible deposited and removed again, which is also referred to as intercalation or de-intercalation. A specific packaging form of lithium-ion cells is referred to as lithium-ion polymer cells or lithium-polymer cell. This is understood to mean lithium-ion cells which are packed in an aluminum composite foil, which in the technical technology is also referred to as a pouch or soft pack.
So that the intercalation or de-intercalation takes place, lithium-ion cells contain an electrolyte. In practice, in all contemporary lithium-ion cells, both in the field of small appliances, for example in the case of cell phones, MP3 players or accumulator-operated tools, as well as in the field of automobiles, for example in the case of hybrid cars (HEV; hybrid electric vehicle), plug-in-hybrid cars (PHEV; plug-in electric vehicle) and electric cars (EV; electric vehicle), these electrolytes are currently composed of the conducting salt lithium hexafluorophosphate (LiPF6) which is dissolved in an organic solvent. Organic carbonates, such as ethylene carbonate (EC) and/or dimethyl carbonate (DMC), are usually used as the solvent. These organic solvent components in the electrolyte are, however, combustible. In addition, in particular volatile solvents can also ignite with air or oxygen or even form explosive mixtures.
For example, in the case of overloading, damage to the cell packaging or unintentional internal or external short-circuiting, lithium-ion cells can heat up to a greater or lesser extent and gaseous, liquid or aerosol cell components can be released when the cell packaging is opened. The cell component in this context can either be non-decomposed combustible cell components, for example electrolytic solvents as well as combustible decomposition products such as carbon monoxide (CO), hydrogen (H2) or methane (CH4).
Document DE 10 2008 059 948 A1 describes a method and a device for preventing and/or fighting fires for a lithium-ion battery in which an extinguishing agent can be temporarily introduced into the interior of the battery via an emergency line from an extinguishing agent accumulator arranged outside the battery housing.